9509550 GIVNISH The plant subfamily Lobelioideae in Hawaii represents one-ninth of the plant species native to Hawaii. There these plants have undergone an amazing radiation with striking specializations in leaf shape, flower form and seed dispersal adaptations. Most species are restricted to individual islands and the species diversity seems to be rapidly disappearing with habitat alterations. Relationships among these Hawaiian species and the group's relationships to other Pacific lobelioids remain controversial. This project will utilize sequence data from both chloroplast and nuclear DNA to construct family trees for the species in the two largest genera of Hawaiian lobelioids and to address relationships to other genera and suggested ancestral groups. Goals of the study include: 1) deriving a molecular based family tree with which to interpret patterns of morphological variation in the Hawaiian lobelioids in a non-circular fashion; 2) determining the amount of agreement between family trees based on molecular data and those previously proposed from morphological data, in order to evaluate the reliability of the morphological traits that have been used to classify the Hawaiian lobelioids; 3) Analyzing the tie between ancestry and distribution and inferring the number of inter-island dispersal events required to account for the diversification seen in the two largest genera; 4) comparing the apparent rates of molecular change in these genera, calibrated against the geological ages of each island, and estimating their approximate time and place of origin; and 5) assessing the relationships of the Hawaiian lobelioids to each other and allied groups to determine if the Hawaiian lobelioids are descended from a single ancestor and identifying which of the proposed groups are implicated in their origin. %%% This study will provide knowledge on the biodiversity and its origins for an important and threatened group of native Hawaiian plants. ***
